identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
924387C5FFF56069FF421A91311CE2B6.text	924387C5FFF56069FF421A91311CE2B6.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Begonia elegantifolia Ritonga, Girm. & Mustaqim 2025	<div><p>Begonia elegantifolia Ritonga, Girm. &amp; Mustaqim, sp. nov.</p><p>§ Platycentrum (Fig. 1.)</p><p>Type:— INDONESIA. Sumatera Utara Province, Langkat Regency, Batang Serangan Subdistrict, <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=98.08914&amp;materialsCitation.latitude=3.6729167" title="Search Plazi for locations around (long 98.08914/lat 3.6729167)">Namu Sialang</a>, 3°40’22.5”N, 98°05’20.9”E, 100 m asl., 10 Oct 2024, Ritonga 1 (holotype: UIDEP; isotype: BO, FIPIA) .</p><p>Diagnosis:— Begonia elegantifolia is unique from other species in sect. Platycentrum by having narrowly lanceolate leaves and staminate flowers with 6 tepals. By its habit and narrowly lanceolate leaves, this species is similar to B. perakensis King (1902: 64), but differs by having leaf surfaces with red bristles (vs. glabrous), staminate flowers with 6 (vs. 4 tepals) and pistillate flowers with 6 tepals (vs. 5). This new species is also similar to Begonia rhoeophila Ridl. (Ridley 1917: 36) in habit but differs by the lanceolate leaf lamina (vs. narrowly lanceolate), base oblique and non-overlapping (vs. narrowed), and flowers with 6 (vs. 5) tepals.</p><p>Lithophytic, monoecious herb, up to 40 cm tall. Stem fleshy, terete, light green, ca. 3 mm in diameter, hirsute, hairs orange-red; rooting around the nodes, distance between leaf clusters 7.4–14.2 cm, each cluster usually with 2 leaves. Stipules lanceolate, red-yellowish red, 0.8–1.2 × 0.2–0.3 cm, apex acute, covered with orange-red hirsute hairs. Leaves asymmetric, lamina narrowly lanceolate, 8.3–17.8 × 2.0– 5.2 cm, apex attenuate, base oblique, margin repand, venation palmate-pinnate, upper surface green, with long orange-red hairs, lower surface pale whitish green, hairy only on veins and veinlets; petiole terete, whitish green, 1.5–10.2 cm long, hairs orange-red. Inflorescence axillary, cymose, 8–12 cm long, bisexual. Staminate flower pedicels terete, c. 16 mm long, light green, sparsely and minutely hairy; bracts yellowish green with a red apex, apex acute, 4–5 × ca. 2 mm; tepals 6, outer ones ovate, 14–16 × 7–9 mm, obtuse or acute, partially hairy outside; inner tepal elliptic, c. 10 × 6 mm, acute, glabrous; androecium yellow, symmetric, subglobose, c. 4.5 × 5 mm, stamens 50–60, filaments c. 0.8 mm long, anthers club-shaped, c. 1 mm long, connective apex rounded, opening by slits. Pistillate flower pedicels terete, 19–22 mm long, light green with sparse minute hairs; bracts 5–6 × 2 mm, yellowish green, tinged with pink, apex acute; ovary light green, with three unequal wings, red hairy, capsule 2-locular, placentae bifid; tepals 6, elliptic-obovate, 1.3–1.7 × 0.9–1.0 cm, white with pink margin, apex acuminate-rounded, sparsely hairy outside; styles 2, stigmas 2, bifid, yellow, twice spirally twisted. Fruit a splash cup pendent on a thin stalk, 19–22 mm long, capsules 13–15 × 18–20 mm, with spreading orange-red hairs, locules 2, wings 3, unequal, larger one falcately ovate, 12–13 mm wide, apex truncate, smaller two rounded, 3–4 mm wide, thick and fleshy.</p><p>Phenology:— Flowering and fruiting recorded in October.</p><p>Distribution and habitat:— Endemic to Sumatra: only known from type locality in Langkat, northern Sumatra. It grows in lowland forest, found around rivers on limestone rocks, 100 to 150 m asl.</p><p>Etymology:— The specific epithet refers to the beautiful shape of the leaf lamina.</p><p>Note:— The extremely narrow leaf lamina is uncommon in the genus Begonia sect. Platycentrum . This feature can be found in Peninsular Malaysian Begonia, i.e. Begonia perakensis and B. rhoeophila . They share the same habitat as B. elegantigolia, growing on rocks around streams. These species also grow in the lowland zone of tropical rainforest in Peninsular Malaysia (Kiew 2005).</p><p>Furthermore, there are 14 species of the section Platycentrum in Sumatra (Hughes et al. 2015 –onwards), where two species are morphologically similar to B. elegantifolia namely B. tuberculosa Girm. (Hughes et al. 2009: 40) and B. areolata Miq. (Miquel 1855: 417). Begonia elegantifolia, however, is easily recognized by its narrowly lanceolate leaves and flowers with six tepals (Table 1). It differs from B. tuberculosa by the absence of small tubers on the fibrous roots (vs. presence), lanceolate (vs. ovate) leaf blades, flowers with tepal 6 (vs. 4 in staminate and 5 in pistillate), and fewer stamens (50–60 vs. 80–100). Begonia tuberculosa is only found in northern Sumatra on Mount Sinabung, Karo, North Sumatra and Mamas River, Southeast Aceh, Aceh from 1200 to 1400 m asl (Hughes et al. 2009, Efendi 2018, Efendi et al. 2020, Girmansyah et al. 2021).</p><p>The new species is also similar to Begonia areolata in sharing opposite leaves below the flowering portion of the stem, but differs by the lanceolate leaf lamina (vs. ovate), narrower leaf (2.1–5.2 cm vs. 10–15 cm wide), with the base oblique and non-overlapping base (vs. cordate with overlapping base), smooth upper leaf surfaces (vs. minutely bullate), flowers with 6 tepals (vs. 4 in staminate and 5–6 in pistillate), fewer stamens (50–60 vs. 137), and gynoecium with 2-celled (vs. 3-celled) ovary as well as 2 stigmas (vs. 2–3 stigmas). Begonia areolata is a much more widespread species found in Sumatra and Java. It grows on forest floors, steep hillsides, and river banks and is found creeping on tree trunks, on elevations up to 2700 meters asl (Girmansyah 2008, Hughes 2008, Efendi et al. 2020, see also Dhiya’ulhaq 2025).</p></div>	https://treatment.plazi.org/id/924387C5FFF56069FF421A91311CE2B6	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Ritonga, Yusran E.;Girmansyah, Deden;Mustaqim, Wendy A.	Ritonga, Yusran E., Girmansyah, Deden, Mustaqim, Wendy A. (2025): Begonia elegantifolia (Begoniaceae), a new species from northern Sumatra, Indonesia. Phytotaxa 720 (1): 87-92, DOI: 10.11646/phytotaxa.720.1.9, URL: https://doi.org/10.11646/phytotaxa.720.1.9
